<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<style>
    .con {
        width: 50px;
        height: 50px;
        border: solid red 30px;
        /*background-color: #bfa;*/
        border-radius: 80%;
        transition:all 0.5s;

        border-top-color: blue;
    }
    .con:hover {
        transform: rotate(160deg);
    }
</style>
<body style="">
<div class="con"></div>
</body>
</html>
